Bolt Extraction Question ; Damper Pin Snapped in 2CV

[ChasR]

Right, I have a bit of a pickle! I'm interested to see what you folks have to say. That includes you as well dollywobbler and greencarfritz

The 2CV is drivable although for not it doesn't half clonk! Why? The driver's side rear damper front pin has snapped within the chassis! It's the thicker end of this that has snapped; the shank of the M14 bit is with the damper but not the threads; these are still in the chassis:



This does of course leave me with a problem. It's snapped below the surface, so that rules out welding something onto the remains. To my knowledge, it's blind on the other side as well.

So, this is how I see my options, besides liberaly soaking the remains in penetrating fluid.

1) Risk a stud extractor/EZ-Out. If this snaps I really will then have a big problem!
2) Try to drift out the remains with a punch; this may take a while.
3) Hope the remains come out with an anti-clockwise drill bit
4) Try to gently hammer out the remains with a punch going anticlockwise; given how deep it has snapped this may not be possible.

For now, I'm going to remove the damper to keep things safe, but I don't know what suggestions you folk have? I'll put some shots up later.

Also, how tight should the new one go in? I've heard reports of 300Nm but that sounds way too tight, even for an M14 bolt.

[v8ian]

if the head has sheared off, you may be lucky and find the bolt as it is no longer tension will come out easily

[steveo3002]

how far below the surface ...might get a washer welded on still?

[winchman]

Start with soaking for as long as you can with plus gas etc, hit the damaged end every day with a punch and big hammer to loosen it.
Left handed drill and a set of these should get it out, its worth fabrication some sort of guide bush to help drill it straight and central
These are sold by Snap on Facom etc but made by Ridgid


www.ridgid.eu/gb/en/10-screw-extractor-set

[ChasR]

Aug 18, 2018 6:29:13 GMT steveo3002 said:

how far below the surface ...might get a washer welded on still?

I'd love to say I could but I have no chance. It's snapped quite a way down. The head of the stud can be seen on the damper .





That extractor set doesn't look too bad! Can they snap like the screw in extractors however?

[winchman]

Yes you can still snap them, you drill it using the guides as big as you can, hammer the splined extractor in and fit the key nut and try to turn it either way, if it wont move you can pull the extractor out and drill bigger or wait whilst the oil works.
I assume you have tried hitting the end with a big punch to loosen it before you start?
Right just re read the thread.
Hit the broken end down the hole with a punch and soak for a bit as this will shock it and allow the oil to get in deeper, leave it as long as you can.
Fabricate a drill guide if you can as its vital to drill it straight and square.
Ring Dormer drills tell them you want a left-handed drill to drill a hardened bolt out, they will give you a part number, buy one and try it about £8 each from memory
Try the LH drill as the drilling forces can loosen it and you night get lucky.
Then if that wont work its extractor time.
Hav eyou a photo of the bit in position on the car as I have a possible idea if it all goes wrong.

[stealthstylz]

I just drill everything out to a size that just cuts into the tops of the female thread then peel the remains out now. Doesn't take much longer even than welding stuff on. Just make sure you start the hole in the middle.

[xbl]

Drill it out gradually then run a tap down it when it's the correct size.

[winchman]

Aug 26, 2018 8:41:55 GMT stealthstylz said:

I just drill everything out to a size that just cuts into the tops of the female thread then peel the remains out now. Doesn't take much longer even than welding stuff on. Just make sure you start the hole in the middle.

This works well but drilling it bang on centre is the difficult bit, I have had a couple wander off!

[chris y]

Aug 27, 2018 6:49:57 GMT winchman said:

Aug 26, 2018 8:41:55 GMT stealthstylz said:

I just drill everything out to a size that just cuts into the tops of the female thread then peel the remains out now. Doesn't take much longer even than welding stuff on. Just make sure you start the hole in the middle.

This works well but drilling it bang on centre is the difficult bit, I have had a couple wander off!

Its what I ususally do too.
It doesnt matter if its not perfectly centred as long as you drill to the size that breaks through in one place, actually it saves potential damage to most of the thread.

Usually once its broken through at one point the its relieved enough to break away all the way around and can be teased out.

[MrSpeedy]

It's very rare that a screw extractor actually works, and if you snap it in the bolt then you really are buggered!

As stealthstylz suggests, drill it out but be sure to get the pilot drill central and square. A bush to guide it can help immensely.

Start out with something like 3/16" and gradually work up until you just cut through the root of the threads and you should be able to pull out the thread like a coil spring

[winchman]

Years ago I heard of a bloke who used to go to firms removing broken bolts, its practice makes perfect, at least you are asking and not rushing in.
As Mr speedy and a few other said a good guide bush is vital, take your time

[ChasR]

Well, after messing around with the W124 I can't leave this car any longer!

I've ordered some left-handed Cobalt drill bits from Irwin. Otherwise, there is a man who can extract the remains locally if he is free.

Hopefully, with the drill bits, perseverence and pressure all will be OK. Part of me is hoping that the drill will screw out the remains. Hopeful I know!